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	Scicom Documentation
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</DIV>    <p>
      <b>analogTrans</b> - 
Transform Analog low pass filter to other types.
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    <h3>
      <font color="blue">Description</font>
    </h3>
Transform a low pass filter to other types, including low pass, high pass, band pass, and bandstop filters.

hst = analogTrans(hs, old_freq, trans_type, new_freq)
hs is a low pass filter's transfer function, with cutoff frequency old_freq(in radius). 
transform the filter to other type of analog filter: low pass, high pass, bandpass band stop.
trans_type is string in 'lp', 'bp', 'bp', 'bs'.
new_freq is new cutoff frequencies. For low pass and high pass, first element is cutoff frequency, others, if any, are ignored.
In the case of bandpass and bandstop, first element is lower cutoff frequency and second element is higher cutoff frequency.
<h3>
      <font color="blue">Examples</font>
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    <pre>

//First design a low pass filter, and then transform it to other types.
//plot magnitude response of original filter and transformed filter.
hs=analpf(4,'cheb1',[.1 0],5)
fr=0:.1:30;
hf=freq(hs(2),hs(3),%i*fr);
hm=abs(hf);
plot(fr,hm);

hst = analogTrans(hs, 5, 'bs', [2,20])
hft = freq(hst(2), hst(3), %i*fr);
hmt = abs(hft);
plot(fr, hmt);

</pre>
    <h3>
      <font color="blue">Used Function</font>
    </h3>analpf, polyval<h3>
      <font color="blue">See Also</font>
    </h3>
    <p>
      <a href="../../../C:/PROGRA~1/BUPT/SCILAB~1.2/man/eng/signal/analpf.htm">
        <tt>
          <b>analpf</b>
        </tt>
      </a>,&nbsp;&nbsp;<a href="polyval.htm">
        <tt>
          <b>polyval</b>
        </tt>
      </a>,&nbsp;&nbsp;</p>
    <h3>
      <font color="blue">Bibliography</font>
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    <h3>
      <font color="blue">Authors</font>
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    <dl>
      <dd>
        <b>BUPT</b>
Zhao Yuan
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